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Hans-Juergen Kochd20620d2007-05-08 17:22:00 +02001Kernel driver max6650
2=====================
3
4Supported chips:
5 * Maxim 6650 / 6651
6 Prefix: 'max6650'
7 Addresses scanned: I2C 0x1b, 0x1f, 0x48, 0x4b
8 Datasheet: http://pdfserv.maxim-ic.com/en/ds/MAX6650-MAX6651.pdf
9
10Authors:
11 Hans J. Koch <hjk@linutronix.de>
12 John Morris <john.morris@spirentcom.com>
13 Claus Gindhart <claus.gindhart@kontron.com>
14
15Description
16-----------
17
18This driver implements support for the Maxim 6650/6651
19
20The 2 devices are very similar, but the Maxim 6550 has a reduced feature
21set, e.g. only one fan-input, instead of 4 for the 6651.
22
23The driver is not able to distinguish between the 2 devices.
24
25The driver provides the following sensor accesses in sysfs:
26
27fan1_input ro fan tachometer speed in RPM
28fan2_input ro "
29fan3_input ro "
30fan4_input ro "
31fan1_target rw desired fan speed in RPM (closed loop mode only)
32pwm1_enable rw regulator mode, 0=full on, 1=open loop, 2=closed loop
33pwm1 rw relative speed (0-255), 255=max. speed.
34 Used in open loop mode only.
35fan1_div rw sets the speed range the inputs can handle. Legal
36 values are 1, 2, 4, and 8. Use lower values for
37 faster fans.
38
39Module parameters
40-----------------
41
42If your board has a BIOS that initializes the MAX6650/6651 correctly, you can
43simply load your module without parameters. It won't touch the configuration
44registers then. If your board BIOS doesn't initialize the chip, or you want
45different settings, you can set the following parameters:
46
47voltage_12V: 5=5V fan, 12=12V fan, 0=don't change
48prescaler: Possible values are 1,2,4,8,16, or 0 for don't change
49clock: The clock frequency in Hz of the chip the driver should assume [254000]
50
51Please have a look at the MAX6650/6651 data sheet and make sure that you fully
52understand the meaning of these parameters before you attempt to change them.
53